Recovery erases treatment debt

A proposed study asks whether recipients who recover after replacement procedures carry hidden damage into the next one, relevant to attempts to slow ageing through repeated tissue or body-part replacement. Its rival hypothesis says recovery clears sequence-dependent biological debt: harm caused by the order of earlier procedures. Apparent worsening could reflect age, injury delivered, imperfect recovery measurement, or selecting recovered survivors. An animal study would randomize schedules and analyse every recipient from the first attempt, recording recovery, death and non-recovery. A clinically negligible history effect, with associations returning only after survivor selection or one noisy measure, would support the hypothesis.